Wash. Rev. Code § 37.16.180
Pursuant to the Constitution and laws of the United States, and especially to paragraph seventeen of section eight of article one of such Constitution, the consent of the legislature of the state of Washington is hereby given to the United States to acquire by donation from any county acting under the provisions of this chapter, title to all the lands herein intended to be referred to, to be evidenced by the deed or deeds of such county, signed by the chair of its board of county commissioners and attested by the clerk of such board under the seal of such board, and the consent of the state of Washington is hereby given to the exercise by the congress of the United States of exclusive legislation in all cases whatsoever, over such tracts or parcels of land so conveyed to it: PROVIDED, Upon such conveyance being concluded, a sufficient description by metes and bounds and an accurate plat or map of each such tract or parcel of land be filed in the auditor's office of the county in which such lands are situated, together with copies of the orders, deeds, patents, or other evidences in writing of the title of the United States: AND PROVIDED, That all civil process issued from the courts of this state, and such criminal process as may issue under the authority of this state against any person charged with crime in cases arising outside of such reservation, may be served and executed thereon in the same mode and manner and by the same officers as if the consent herein given had not been made.
RCW 37.16.180
General cession of jurisdiction: Chapter 37.04 RCW.
Jurisdiction in special cases: Chapter 37.08 RCW.